Two GPUs driver problem

So I'm coming with one more, however different, problem.

I "repaired" (new Mobo) my PC. The differences with before are Mobo (F1A55-V in place of F1A55-M LX) and CPU (A8-3870K in place of Athlon II x4 641.

Everything works fine, except GPUs. Or closer, the drivers...

Before I had only HD7770. Now I have adfitionally HD6550D as integrated GPU.

After first OS boot, both GPUs are active. However drivers are from 2015...
After updating the HD7770 with latest driverd (April 2019 ones) Windows disables iGPU with error 43 in Device Manager...

HD7770 is always active. It's enough, but I wanted to have them both active and one of the displays connected to Mobos VGA/DVI port.

I tried installing with and without AMD Settings. Both using Installer and through DevMgr.

Any way to have both of them working? Any ideas?

Are you running just the one monitor?

If so, connect to the GPU you want to use, uninstall ALL GPU drivers and restart.

This should put the drivers to a default state.

Then install the GPU drivers from the manufactures website.

I have two monitors, but even when using only one, after installing newer drivers for HD7770, I'm always ending with disabled iGPU.

It seems like the drivers are incompatible with HD6550D. However how when it's not being updated?

So now I use only HD7770. HD6550D is disabled. However I'm missing AMD Software. How to install it? But only Software without reinstalling drivers?

Tried AMD Installer, but it "thinks" and "thinks" and nothing changes... I think I could wait forever and it wouldn't find devices express instalattion) or drivers (custom one)